Fig. 4

Enhancing effects of ARE (a) and ARE-F (b) on the total GSH attenuation in HaCaT keratinocytes under UV-B irradiation. HaCaT cells were subjected to the varying concentrations (0, 5, 20 and 80 μg/mL) of ARE (a) and ARE-F (b) for 1 h before the irradiation. The total GSH content in the cellular lysates, quantitated with an enzymatic recycling assay using GR, was expressed as a percentage (%) of the corresponding non-irradiated control. ##P < 0.01; ###P < 0.001 versus the non-irradiated control. *P < 0.05; **P < 0.01; ***P < 0.001 versus the non-treated control (UV-B irradiation alone)